集输管路上升管系统严重段塞流实验和理论模拟

EXPERIMENTAL INVESTIGATION AND SIMULATION OF SEVERE SLUGGING IN PIPELINE-RISER SYSTEM

严重段塞流的实验研究表明,在气泡进入上升管底部到运动至出口的过程中,上升管中气泡头部以下流型为弹状流型;当气泡头部流出上升管后,上升管中的流型可看作块状流型。根据实验结果,本文提出了采用漂移流模型简化计算上升管中两相流动、上游管道中气体膨胀满足质量守恒,同时考虑上升管内液体动量守恒的严重段塞流计算模型。计算值与测量值比较表明,模型可以正确预测出气体膨胀流动过程,气体流动时间不受入口气液流量的影响。模型可以准确计算出严重段塞流周期、液塞长度和倾斜管中液柱最大长度等参数。

From the observations of severe slugging carried out on a laboratory facility, it was found that the flow pattern of gas-liquid flow behind the Taylor bubble front in the riser at the bubble penetration stage was slug flow, and the churn flow existed in the riser at the gas blowout stage. Based on these observations, a new theoretical model was developed to predict the characteristics of gas-liquid flow in the pipeline-riser system, in which the two-phase flow behavior in the riser was predicted by a drift-flux model, and the mass conservation of gas in the pipeline and the momentum conservation of the liquid between the Taylor bubble front and the top of the riser was considered. Compared to the experimental results, it was verified that the present model predicted accurately the process of gas flow in the pipeline and riser and the system variables such as pressure transients, cycle time, liquid slug length and liquid accumulation.